1. Field of the Invention:
This invention relates to friction facings for friction clutches, brakes and the like, and more particularly to such friction facings which are made from non-woven fabrics or paper.
2. Description of the Prior Art:
Friction facings for friction clutches, brake linings and the like are frequently composed of a relatively thin layer of non-woven fabric or paper prepared by standard papermaking techniques using a paper making machine. The fibrous lamina is then impregnated with a curable binder composition, formed and cured using heat and pressure, and finally polished, thereby to prepare a finished friction facing. Friction facings prepared in this way are generally used in the clutch facings and brake linings of motor vehicles.
However, the friction facings prepared by the hitherto known process have been found to have certain drawbacks. Fibrous laminae prepared by the usual papermaking techniques have their fibers oriented predominantely in the plane of the lamina. Thus, the laminae containing fibers so oriented have little strength in a direction perpendicular to the plane of the lamina, and they are prone to separate in that direction, producing delamination of the friction facing. This is evidently an undesirable property of such friction facings. Thus, impregnated friction facings prepared by the hitherto conventional process are deficient in their properties.
Hence, a need has continued to exist for an improved friction facing which is not subject to the problems of delamination.